New Defender's Study Bible Notes
15:51 a mystery. This “mystery,” not revealed in previous ages, assures us that Christ’s second coming will be initiated by simultaneous resurrection and glorification of the dead in Christ and glorification of the bodies of those still living at the time. Note that all will be raised! There is no basis for the so-called “partial rapture” theory. This same mystery had been unveiled previously to the Thessalonian believers (I Thessalonians 4:13-17), but his epistle to that church did not include the more detailed specifications for the spiritual body as described here. That body would be immortal (that is, no longer subject to death) and incorruptible (that is, no longer subject even to decay, pain, disease, or other physical effects of the curse). Paul would soon point out essentially this same truth to the churches at Philippi (Philippians 3:20-21) and Colosse (Colossians 3:4). In none of these is there any instruction to look first for the Antichrist, or the great tribulation, or for anything except Christ Himself!
15:52 In a moment. “Moment” is the Greek atomos, believed at that time to be the very smallest particle of matter. The coming of Christ is to be very sudden, and without advance notice, so that we should be “abiding in Him” at all times. See I John 2:28; Hebrews 9:28; II Timothy 4:8.
15:52 the last trump. Paul is not referring to the last of the seven trumpets in the Apocalypse (Revelation 8:2; 11:15), for the book of Revelation had not yet been written and Paul obviously intended for the Corinthians to understand what he meant. The sounding of an angelic trumpet at the resurrection day had also been mentioned in I Thessalonians 4:16. Trumpets were traditionally associated with calls to action (e.g., I Corinthians 14:8; Judges 7:20), and this particular trumpet sounded in heaven will call all saints, living and dead, to ascend into heaven to meet the returning Christ. It is, therefore, “the last trump” of this present age of the church.